Application of Hidden Markov Models and Hidden Semi Markov Models as Diagnostic Aid in Chronic Mastitis in Cows

Safeer M. Saifudeen; R. Venkataramanan; A. Serma Saravana Pandian

Authors

Safeer M. Saifudeen Department of Animal Husbandry Statistics and Computer Applications, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, Tamil Nadu, INDIA
R. Venkataramanan Department of Animal Husbandry Statistics and Computer Applications, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, Tamil Nadu, INDIA
A. Serma Saravana Pandian Department of Animal Husbandry Statistics and Computer Applications, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai, Tamil Nadu, INDIA

Keywords:

Chronic Mastitis, Inflammation, Hidden Markov Model, Hidden Semi Markov Model, Symptoms

Abstract

Mastitis is the most important and expensive disease of dairy industry. The present study was conducted at the Large Animal Clinic of Madras Veterinary College Hospital, Chennai from November 2016 to March 2017 to find out the most probable sequence of stages of chronic mastitis. Analysis of HMM and HSMM were performed using ‘The R Project for Statistical Computing’ (version 3.4.0). The study summarized as disease started with stage of bacterial entry and its flare up (W1) with reduced milk production and presence of watery milk from the lactating quarters. As the time advanced, the disease progressed to the stage of increasing somatic cell count (W2) where repeated episodes of sub-acute mastitis could be seen. The stage of fibrous tissue proliferation is visible only in the case of hidden semi Markov model (HSMM). These models might be used in decision making process like, either maintenance or culling of the affected animals in established farms.